Tourette syndrome (TS) is a childhood-onset neuropsychiatric disorder. In over half of cases tics improve or remit during adolescence. However, the most severe symptoms of TS are usually seen in adulthood. In this career development award we will conduct a longitudinal structural neuroimaging that follows children with TS to young adulthood. Our goal is to compare the brain development in persistent TS cases to remitted cases and unaffected controls. Michael H. Bloch, M.D., M.S., the candidate for this career development award, has spent the last 10 years researching and treating TS and related disorders at Yale first as a medical student and then in psychiatry residency. He will complete his child and adult psychiatry training in the Albert J., Solnit Integrated Training Program at the Yale Child Study Center in June 2010. The Albert J. Solnit Training Program is a novel combined six-year child and adult psychiatry residency program that combines clinical and research training. Based on his clinical expertise, he was appointed as Assistant Director of the Yale OCD Clinic after his third year of residency. He has also completed a graduate degree in chronic disease epidemiology from the Yale School of Public Health during his residency program. He has already published over 20 peer-reviewed publications in TS and related disorder during his residency training including first-authored publications in the American Journal of Psychiatry, Molecular Psychiatry, JAACAP, Neurology and Biological Psychiatry. The majority of these articles were published under the mentorship of James F. Leckman M.D. and Bradley S. Peterson, M.D., who are the proposed mentors for this K award. The candidate plans to become an independent investigator in developmental neuroimaging of TS and related disorders at the completion of his awards period. He plans to get training and mentorship in structural neuroimaging during the career development award period. We have followed a cohort of 46 children diagnosed with TS to young adulthood. Each of these children received a detailed clinical assessment, structural neuroimaging and focused neuropsychological testing prior to age 14 years. We have published several manuscripts on this demonstrated in this cohort that smaller childhood caudate volumes were associated with increased tic symptoms in young adulthood. Our goals are to (1) examine the association of childhood basal ganglia morphology and childhood cortical thickness measures and adulthood tic severity and (2) repeat structural neuroimaging scans on these subjects so that we can compare brain development between persistent TS cases, remitted TS cases and unaffected controls.